Katie Miller, once a top doctor in the cardiovascular field, left the medical profession after her marriage failed. She is now back in the workforce as director of Mercy Grace Hospital. However, only Katie Miller can save the son of her ex-husband Derek Walsh. In the face of her ex-husband's cynicism,Katie Miller was appointed in a crisis, showing amazing medical skills. Under pressure, she must not only prove her professional competence, but also protect her daughter from harm. This operation is not only about the life of a child, but also a key moment for Katie Miller to reshape herself and prove her value.